Rosenfels left a long and meaningful note on his Facebook page in explaining the decision. He even thanked a sports writer.

“I always knew the day would come,” he wrote. “I just didn’t think I’d be 35 when it finally happened. I will soon be turning in my paperwork to the NFL and formally retiring after a 12 year career. Like most NFL players, I wish I could have played a couple more seasons, but usually the league is done with you before you are done with it.

“It definitely was a roller coaster ride with many ups and downs and not a lot of years where I felt comfortable with my standing on a team. A dozen years of battling every day to make it another year and to prove myself against some of the best athletes in the world.”